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http://purl.uniprot.org/citations/14561230http://www.w3.org/1999/02/22-rdf-syntax-ns#typehttp://purl.uniprot.org/core/Journal_Citation
http://purl.uniprot.org/citations/14561230http://www.w3.org/2000/01/rdf-schema#comment"

Background

Aquaporin-1 (AQP1) functions as an osmotic water channel and a gated cation channel. Activation of the AQP1 ion conductance by intracellular cGMP was hypothesized to involve the carboxyl (C-) terminus, based on amino acid sequence alignments with cyclic-nucleotide-gated channels and cGMP-selective phosphodiesterases.

Results

Voltage clamp analyses of human AQP1 channels expressed in Xenopus oocytes demonstrated that the nitric oxide donor, sodium nitroprusside (SNP; 3-14 mM) activated the ionic conductance response in a dose-dependent manner. Block of soluble guanylate cyclase prevented the response. Enzyme immunoassays confirmed a linear dose-dependent relationship between SNP and the resulting intracellular cGMP levels (up to 1700 fmol cGMP /oocyte at 14 mM SNP). Results here are the first to show that the efficacy of ion channel activation is decreased by mutations of AQP1 at conserved residues in the C-terminal domain (aspartate D237 and lysine K243).

Conclusions

These data support the idea that the limited amino acid sequence similarities found between three diverse classes of cGMP-binding proteins are significant to the function of AQP1 as a cGMP-gated ion channel, and provide direct evidence for the involvement of the AQP1 C-terminal domain in cGMP-mediated ion channel activation."xsd:string
http://purl.uniprot.org/citations/14561230http://purl.org/dc/terms/identifier"doi:10.1186/1472-6793-3-12"xsd:string
http://purl.uniprot.org/citations/14561230http://purl.uniprot.org/core/author"Yool A.J."xsd:string
http://purl.uniprot.org/citations/14561230http://purl.uniprot.org/core/author"Boassa D."xsd:string
http://purl.uniprot.org/citations/14561230http://purl.uniprot.org/core/date"2003"xsd:gYear
http://purl.uniprot.org/citations/14561230http://purl.uniprot.org/core/name"BMC Physiol"xsd:string
http://purl.uniprot.org/citations/14561230http://purl.uniprot.org/core/pages"12"xsd:string
http://purl.uniprot.org/citations/14561230http://purl.uniprot.org/core/title"Single amino acids in the carboxyl terminal domain of aquaporin-1 contribute to cGMP-dependent ion channel activation."xsd:string
http://purl.uniprot.org/citations/14561230http://purl.uniprot.org/core/volume"3"xsd:string
http://purl.uniprot.org/citations/14561230http://www.w3.org/2004/02/skos/core#exactMatchhttp://purl.uniprot.org/pubmed/14561230
http://purl.uniprot.org/citations/14561230http://xmlns.com/foaf/0.1/primaryTopicOfhttps://pubmed.ncbi.nlm.nih.gov/14561230
http://purl.uniprot.org/uniprot/P29972#attribution-EFA860D284FA2520931D1C5028F608C3http://purl.uniprot.org/core/sourcehttp://purl.uniprot.org/citations/14561230